Relief printing method



Sept. 21,1937; K. SCHILIEIDER 2,093,485

RELIEF PRINTING METHOD Filed June 11, 1956 .v/ -J l/l/ INVENTOR. KARLSCHNEIDER ATTORNEY Patented Sept. 21, 1937 Application June 11, 1936,Serial No. 84,599 In Germany May 17, 1935 This invention relates to arelief printing method employing elastic means for carrying the matterto be printed.

In the application of the known processes either ,caoutchouc forms as,in aniline printing or metal forms coated with rubber are used. Comparedwith the known methods, the invention proposes simply to apply a thinfilm of elastic or fiexible material, particularly caoutchouc, totheform, the film being sucked on by means of a'high vacuum and thus sofirmly and completely drawn and adapted to the form that the outlines ofthe carrier of the matter to be printed and all unevenesses of the formdistinctly reappear on the surface of the film.

The essential technical difference between the known methods and themethod according to the invention is therefore chiefly this, that theformer employ forms which are either made of elastic material or whereinthe latter is firmly united with the form, whereas according to theinvention the elastic material is intimately but not firmly associatedwith the form. The new method affords considerable technical advantages.In the first place, the production of a vacuum form as proposed by theinvention is much simpler than that of the forms hitherto employed inprinting with elastic printing matter carriers. Furthermore,-the formaccording to the invention can be readily altered during printing,which'is not possible with forms of the existing kind. An-

other important feature is that easily workable and low-priced materialsof any kind may be used in making a vacuum form, including those thatusually are never considered for this purpose. The use of the new forms,finally, affords novel possibilities in the printing art, as forinstance large surfaces can be entirely printed with .liefprinting.

a to

the new forms on standard printing machines,-

which up to the present was not possible in re- The application of themethod is explained below with reference to a monochromatic printwithout tone values, such as a poster. For making the printing form thematter or characters to be printed, such as letters, figures, etc., aretransferred to a suitable material of uniform thickness like cardboard,sheet metal, etc. and worked out. The transfer of the matter and theworking out of the; carrier therefor may be effected by the usualtechnical means, but also by hand, for in-- stance byetching, embossing,cutting out, etc. The carriers of the matter are then placed on afoundation surface and covered with the thin elastic film, whereupon theair between the carriers and the film is sucked off by known means.

Owing to the vacuum produced, the film, by exterior atmosphericpressure, is firmly pressed onto the form and the foundation bearing-thelatter but not cooperating in printing, so that the film becomesperfectly adapted'to the outlines. In this manner it will be possible toconvert even materials which usually cannot be employed for carriers butwhich are much cheaper than the a usual ones, such as blotting paper,sand paper,

textiles, into a finished printing form, whereby production may beconsiderably simplified and cheapened. The elastic film pressed on bythe vacuum is so firmly applied to the foundation and the carriers ofthe matter to be printed that the-latter are thoroughly pressed on tothe foundation and need not be specially fastened thereto by pasting,etc.

The form thus produced is shown in one embodiment in the accompanyingdrawing which discloses a perspective view thereof, partly in section.

Referring to the drawing, l is the foundation consisting preferably of asolid piece of metal, though it may comprise also several parts. Thefoundation i contains one or more longitudinal channels 2 whence outletconduits' 3 lead to the surface of the foundation. The printing form 4is placed on the perfectly smooth surface of the foundation i and mayconsist .of a piece of cardboard or sheet metal treated in intaglio orembossed or cut out according to the matter to be printed, or which maycomprise a plurality of parts having the effect of cuts. Besides sheetmetal or cardboard, any other material possessing suflicient strengthmay be employed'for producing the form, and it is therefore possible touse for instance wires 40. to produce lines in printing. Over thesesheets or parts producing the impression a very thin elastic film 5 isput the edges of which are preferably pasted onto the free surface ofthe foundation. The surface of the foundation and the film 5 form aclosed space whence air is drawn off by the conduits 2 and 3. Thedrawingoff of the air causes the film 5 tobe so firmly pressed againstthe foundation and the parts lying thereon by atmospheric pres-- surethat the finest details of the parts as well is rough or fitted withelevations like sand paper. The intermediate layerwill also render thesuction effect more uniform.

In case of a monochromatic print having different tone values theimpression producing matter is transferred as described, but worked outin relief corresponding to the necessary toning in a manner similarly tothe one employed in copperplate printing. Owing to the different levelswithin the relief, different printing effects will be produced and bringabout the desired tone values by the peculiarity of the elastic film. Inthis way full depths up to the finest gradations are obtainable withoutthe use of screens.

In multi-color work the invention is applied to the color sheetsproduced in the usual manner.

The technical and economic advantages afforded by the new method arevery considerable. Instead of the type, rules, cuts of metal or wood,linoleum engravings, etc. hitherto employed in the composing roomprinting forms may be used which may cheaply and simply be made forinstance by cutting them out of cardboard or by resorting to materialsthat could not be used in printing till now. Even tonedprinting mattercarriers not too rich in detail can be attained by hand cutting bybuilding them up step for step according to the tone value. The methodaccording to the invention can further be applied to obtain in an easymanner certain designs by interposing for instance corresponding layers,such as apiece of curtain, between the form and the elastic film.

After removal of the vacuum and the film the carriers of the matter tobe printed are freely accessible to insure exact register and to makechanges, and after completion of printing they may be put away forfuture use like other forms.

The elastic film easily adapts itself also to the unevennesses of thematerial on which the impression is to be made, so that printing can bedone with less color'and without making ready and interleaving may bedispensed with.

method can be carried out on both flat and ary machines. In specialinstances, when cider machines are concerned, it might be advisable tocover also the cylinder with an elastic coating to render the methodmore eflective.

I claim: I

1. A printing device comprising a character, a separate flexible sheet,and suction means for releasably and intimately uniting the sheet withthe character whereby the contour of the latter is transmitted to thesheet presenting a printing surface.

2. A printing device comprising a character, a separate flexible sheet,and means for releasably and intimately uniting the sheet with thecharacter whereby the contour of the latter is transmitted to the sheetpresenting a printing surface.

3. A printing device comprising a base, a character, a separate elasticfilm, and'means for releasably and intimately uniting the film with thebase and character whereby the contour of the character is transmittedto the film presenting a printing surface.

4. A printing device comprising a base, a character, a flexible sheet,and suction means, said means being operable for fixing the character onthe base, and for intimately uniting the sheet with the character topresent a printing surface substantially having the contour of thecharacter.

5. A printing device comprising a character, a thin flexible sheetpresenting a printing surface, and means for releasably impelling thesaid sheet into intimate contact with said character whereby the contourof the character may be transmitted to said surface.

6. A printing device comprising a base, a character upon a surface ofsaid base, a flexible film over and removable from said character, andmeans to intimately and removably unite said film to said character,said means including a passageway in said base connecting with its saidsurface and means to evacuate air through said passageway.

7. A printing device comprising a base. a character associated with saidbase, a plate intermediate said base and said character, said platehaving a roughened surface, a thin flexible sheet over said characterand said base and presenting a printing surface, and suction means forreleasably holding thebase, plate, character and sheet in respectiveintimate contact and whereby the contour of the character is transmittedto said surface, said plate facilitating the suction efiect.

8. A printing device comprising a base, a character on said base, afilm, and a flexible layer having a predetermined pattern or designdisposed between said film and said character, said film intimatelycovering said character whereby the sheet substantially simulates thecontour of the character.

9. A printing device comprising a base, a character on said base, afilm, a flexible layer having a predetermined pattern or design disposedbetween said fllm and said character, and means to releasably securesaid film to said layer, said means including a passageway in said baseleading to a surface thereof and means to exhaust I substantiallysimulates the contour of the character.

12. A printing device comprising a base, a character associated withsaid base, said character being made of fibrous material, a separatethin flexible sheet covering said character, and means to releasablysecure said film to said base,

said means including a passageway in said base leading to a surfacethereof and means to exhaust air throughsaid passageway.

13. The method of producing a device for printing which consists ininterposing a character between a flexible film and. a base andexhausting the air from between said film and base whereby the characteris forced into relief.

' 14. The method of producing a device for printing which consists inplacing a flexible film over a character and causing the film to beintimately united to the character by exhausting air therebetween,whereby the contour .of the character is transmitted to said film.

KARL SCHNEIDER.

